Demulsification of a synthetic water in oil(W/O)crude oil emulsion was studied by measuring wate-oil interfacial properties such as life time and thinning rate of oil film in the presence of various demulsifiers.The results indicated that the interfacial elasticity decreased both the strength and the life time of oil film and film thickness when adding the demulsifiers.The oil film broke when film thickness came to a critical level.As for a demulsifier,the interfacial elasticity was decreased with demulsifier concentration increase, and stayed constant above a critical demulsifier concentration.The rate of dewatering is related to interfacial elasticity.When different demulsifiers were compared,the more the interfacial elasticity was lowered,the more efficient was the dewatering.The mechanism of the different types of demulsifiers was discussed based on the experimental results.The demulsifiers partially replaced the emulsifiers,which led to the interfacial elasticity decreased.The effect of chemical structure of the demulsifiers on water-oil interfacial film was studied.

The interfacial tensions between solutions containing NaOH and ORS-41,and crude oil were demonstrated to be a function of the two components.Surfactant ORS-41 film characteristics changed as a function of the alkali concentration showing interactions between alkali and surfactant.The polyacrylamide has little effect on the surfactant monolayer at high surface pressure,but has considerable effect at low surface pressure.The w:o emulsion stability was kinetically determined through the use of the conventional bottle test.Both surfactant and alkali has a significant effect on emulsion stability.Polymer has little effect on the emulsion stability at higher ORS-41 concentrations.Emulsion stability varied as a result of chemical interactions effecting interfacial tension and interfacial film strength.

研究了破乳剂存在下油膜寿命、油膜薄化速率以及油水界面性质与破乳效果的关系。结果表明，破乳剂使油水界面弹性降低，导致油水界面强度减弱，界面膜寿命变短，界面膜厚度变薄。当膜厚度变薄到一临界值时，膜破裂，导致破乳脱水。同种破乳剂，随着其浓度的增加，界面弹性降低。当浓度超过某一值时，界面弹性值基本不变。不同种破乳剂，界面弹性降低幅度越大，其破乳效果越好。界面弹性值可以很好解释破乳剂的脱水率变化规律。

研究了煤油与原油配制模拟油乳状液的稳定性，应用显微镜测定了模拟油乳状液粒子的粒径。实验确定了配制模拟油乳状液的最佳原油与煤油比、乳化速度、乳化时间和油水比。对破乳剂OX-9354和OX-9351在模拟油与原油乳状液中的脱水情况进行了对比，表明脱水率变化趋势相同，模拟油可以用来评价破乳剂。

Resin and asphaltene were separated from Daqing crude oil and were dissolved in decane1 The interfacial viscoelasticity was investigated by applying the cont rolled stress model of oscillatory ring interfacial rheometer CIR-100.The effects of resin,asphaltene contents in decane,pH values,and demulsifiers in aqueous phase on interfacial viscoelasticity were studied1 It was shown the interfacial viscoelasticity of water/decane containing asphaltenes or resins is of the order of 4 higher than that of water/decane,and the interfacial viscoelasticity increased with increasing resin and asphaltene concent rations in decane.When the pH value in aqueous phase was about 7,interfacial elasticity approached a maximum1 Demulsifers in aqueous phase could obviously reduce interfacial viscoelasticity and interfacial tension.